There was an extraordinary day at the US Open on Saturday as many anticipated Novak Djokovic and Roger Federer to set up a marquee final. However, there will be a first-time Grand Slam champion on Monday as two upsets played out in the semifinals.

Nishikori Upsets Djokovic, Advances to Final

The first semifinal featured a man making his first Grand Slam semifinal appearance, facing a man who is a regular. Kei Nishikori faced Novak Djokovic with the winner to advance to Monday's championship match. And after eliminating the fifth and third seeds, Nishikori defeated top-seeded Djokovic 6-4 1-6 7-6 6-3.

In the opening set, it was Nishikori finding the first opening, breaking the Serb in his second service game. However, in the following game, Djokovic emphatically pushed play back on serve by breaking the Japanese star. As the set progressed, it was the 10th seed who combined quickness with generating effective power as he applied pressure and dictated points. Having controlled the top seed with his play, Nishikori closed out the first set on his serve.

In the second set, a few tight groundstrokes by Nishikori opened the door for the 2011 U. S. Open champion, who broke serve early. Despite placing less than 50 percent of his first serves in play, Djokovic dictated play. The veteran sensed his opportunity to even the match and rolled to a quick second-set win.

In the third set, Nishikori appeared to be experiencing the effects of fatigue as he aimed to shorten points early. With the 10th seed coming off back-to-back matches that surpassed the four-hour mark, coupled with a hot day in New York, he showed outward signs of exhaustion. Perhaps sensing this, Djokovic attacked his serve while attempting to pump up the crowd. However, the Japanese player held serve in a key moment of the set after a grueling 20-point game to go to 2-1. Much like a prize fighter who was saved by the bell after clinging to the ropes, Nishikori gutted his way to a changeover break after a mentally and physically challenging game.

As the heat continued to be a factor, both players placed emphasis on service games. Interestingly, although Djokovic appeared to be the fresher player, it was Nishikori who found the crack in his opponent’s serve, breaking once more. Yet big-time champions come up with big-time shots, and Djokovic did not disappoint, forcing a third-set tiebreak.

In the tiebreak, it was Nishikori who excelled once more, taking the set after a 7-4 result.

Now, into the fourth set, it was Djokovic who showed signs of fatigue as Nishikori found a second wind. He broke the seven-time Grand Slam champion immediately. Djokovic, now desperate for a service break, found no success chipping away at the Nishikori serve. Then, with the Serb serving at 3-5 and needing to hold his serve to stay in the match, it was Nishikori who found two match points. On the second chance, it was the 10th seed, scrambling and scrapping his way on match point to break service to complete the upset.

“It's just amazing, an amazing feeling beating the No. 1 player,” Nishikori said. Reflecting on his decision to enter the tournament despite an ailing foot, he commented, “I didn't even know if I should come to New York, so I wasn't expecting anything actually. But after playing first match and second match, I go more confidence on my foot, and it was no pain at the moments. I started sliding little more. But my tennis was there already. I was really trying to play one match at a time, and now I'm here.”

Later, Djokovic weighed in, “He just played better in these conditions than I did. I just wasn't managing to go through the ball in the court. I wasn't balanced. Even when the ball got back to his part of the court, it was pretty short. He took advantage of it. On the other side, I didn't.”

Upsets Continue: Cilic Eliminates Federer

After a short rain delay, second seed Roger Federer met 14th seed Marin Cilic in the second men's semifinal. And for a second straight match in Ashe Stadium, there was an upset. Cilic defeated Federer in straight sets 6-3 6-4 6-4.

The big-hitting Croat began play with confidence, striking solid and consistent groundstrokes. In the first set, Cilic played cleanly despite his power-hitting style. Interestingly, it is Cilic who is known for his big serve, yet it was Federer who fired five aces and had a much higher first-serve percentage in the set. Regardless, it was the Croatian who struck 15 winners and gained the one break he would need as he served out the first set to take the lead.

In the second, with the partisan Federer crowd becoming anxious, Cilic broke the five-time U. S. Open champion early. Creating sharp angles with power off of his forehand, he refused to let Federer near a service break early in the set. The Swiss champion attempted to slice low and deep backhands, hoping to create difficulty for the 6'6” Croat. The strategy showed signs of success, but suddenly Cilic's serve heated up. Behind that serve and a number of errors off the Federer backhand, it was the 25-year-old taking the second set in a fast-paced match.

For the second straight match, Federer would be forced to win three consecutive sets to keep alive the opportunity to earn his 18th major title. However, he would have the full barrage of the extremely vocal New York crowd behind him.

At the urging of those fans, Federer picked up the momentum and sense of urgency quickly in the third set, when he gained an early break. However, the cool Croat was unfazed by the fervor of the crowd and steadily earned his break back. Keeping Federer off balance with his robust groundstrokes, Cilic would gain another break of service to take a 4-3 lead in the set. Impressively, his composure and consistency left no window open for the 33-year-old Swiss. And as an exclamation mark, he closed the match out with three straight aces followed by a crisp backhand winner in impressive fashion.

“It's an amazing day for me. I feel amazing,” said Cilic. “To be able to play like this, I never dreamed of it. I think today was my best performance ever in my career.”

Federer made no excuses. “I was feeling good. I just think if I could have stayed longer with him in the first set, I felt like there was a proper match going on. But when Cilic was playing with the lead, he played with no fear and just full-out confidence. He served great when he had to. Credit to him for just playing incredible tennis.”

It will be the first time since the 2005 US Open that a Grand Slam final will not include Djokovic, Federer, Rafael Nadal, or Andy Murray.